The race for National League Rookie of the Year continues to be a two-man competition between Arizona Diamondbacks pitcher Wade Miley and Cincinnati Reds infielder Todd Frazier.

Neither player had a particularly good week since our last set of rankings, but both have established themselves enough to hold off any sort of charge from the other top contenders.

Two rookies who could work their way into the top five before the end of September, however, are Chicago Cubs first baseman Anthony Rizzo and Washington Nationals outfielder Bryce Harper. Both players have been swinging hot bats so far this month.

Harper, in particular, has been sizzling in September. Those who preferred to exclude him from awards discussion may have to deal with him earning strong consideration again.

However, the following five players look like the current leading contenders for NL Rookie of the Year honors. There's been a little shuffling among the top five this week.

Is anyone being overlooked or overhyped in your view? Please leave your responses and suggestions in the comments. You can also reply to me on Twitter. My address is at the end of this article. Your feedback often plays a role in how these rankings are put together each week.

5. Lucas Harrell, Houston Astros

After allowing only one run in each of his previous two starts, Lucas Harrell gave up three runs in his most recent appearance.

Pitching against the Cincinnati Reds on Sept. 7, Harrell allowed seven hits and four walks in addition to those three runs. It was his highest walk total in his past six starts.

But facing the Reds in back-to-back appearances could not have been easy for a rookie pitcher. In the second of those two starts, pitching at Great American Ball Park, Cincinnati's batters surely would have figured Harrell out, right?

Harrell didn't get a decision in either game, but pitched well enough to win both times. He allowed a total of four runs and 14 hits in 13 innings, adding five walks and eight strikeouts.

One of the most amusing stats with Harrell continues to be him having 10 of the Astros' 45 wins this season. How many pitchers have accounted for 22 percent of their team's wins? R.A. Dickey of the Mets has 18 of the New York Mets' 65 wins this season, accounting for 28 percent of his team's victories.

Far more impressive, however, is Harrell's 2.06 ERA in 11 home starts at Minute Maid Park.

It's hoped that Cozart will return to the Reds lineup by the end of this week, but that appears to be optimistic.

Cozart had a strong August, batting .267 with a .763 OPS. He compiled 10 doubles, five home runs and 11 RBI. Yet his .243 average for the season and .686 OPS rank him far below his fellow NL rookies.

But Reds manager Dusty Baker has kept Cozart in the lineup because of his defense. According to FanGraphs' Ultimate Zone Rating, Cozart is the second-best defensive shortstop in the NL, saving the Reds six runs more than the average fielder at that position.

3. Wilin Rosario, Colorado Rockies

With Zack Cozart sliding due to injury, Wilin Rosario moves up one spot in the NL Rookie of the Year rankings.

In seven games since last week's rankings, Rosario hit 6-for-25 (.240) and drove in two runs. That moved him to within two RBI of Todd Frazier's NL rookie lead.

Rosario continues to lead all NL first-year players in home runs with 23, five more than the next closest competitor. Though if Bryce Harper keeps hitting the way he has in September, perhaps he can challenge Rosario for the NL rookie home run crown.

During the final three weeks of the season, the Colorado Rockies' rookie catcher will surely try to improve his defense behind the plate.

Rosario has allowed 47 wild pitches, the second-highest total among catchers with 700 innings. His 19 passed balls allowed are the most in the majors.

However, he does a good job throwing out opposing runners, gunning down 62 percent (29-of-47) of attempted base stealers this season.

2. Todd Frazier, Cincinnati Reds

After an excellent August in which he hit .330 with a .981 OPS, adding six home runs and 25 RBI, Todd Frazier has scuffled thus far in September.

In 38 plate appearances, Frazier is batting .176 with a .440 OPS, no extra-base hits and no runs driven in.

The Reds rookie infielder might not have as many opportunities to right himself at the plate during September either, as the return of Joey Votto and Scott Rolen from injury will reduce the number of at-bats he receives.

With Zack Cozart's injury leaving a hole at shortstop, the Cincinnati Enquirer's John Fay asked Reds manager Dusty Baker whether he might consider playing Frazier there to keep his bat in the lineup. That led to the following response:

“They didn’t move him off short for nothing. Am I right? If he was a shortstop, he’d still be there. They moved him to first, they moved him right, they moved him to left. They were looking for a position for him. You just don’t throw anybody at shortstop. That’s probably the toughest, most-athletic position on the field.”

But Frazier played 112 games at shortstop in the minors, the second-most games he played at any position. That's why Fay asked the question.

Baker may dismiss the suggestion now, but if Cozart stays out with his oblique injury, the Reds might have to play Frazier at shortstop to generate some offense at the position.

1. Wade Miley, Arizona Diamondbacks

Christopher Hanewinckel-US PRESSWIRE

Last week: No. 1.

Wade Miley was roughed up for one of his worst starts of the season by the surging San Diego Padres in his most recent appearance.

The Arizona Diamondbacks left-hander allowed five runs and eight hits in 5.1 innings, issuing a season-high three walks. The fact that three walks is the most Miley has allowed in a game this year shows you how outstanding his control has been and how much he prefers to pound the strike zone.

That performance increased Miley's ERA from 2.90 to 3.07, but that still places him among the top 10 NL starting pitchers in that category. His 1.15 WHIP (walk and hits per innings pitched) is also one of the 10 best in the league at this point of the season.

Opposing batters are hitting .248 against him, but since Miley walks only 1.7 hitters per nine innings (the fifth-best rate among NL starting pitchers), he keeps runs to a minimum.

The D-Backs are still on the fringe of the NL playoff race, five games back in the wild-card standings as of Sept. 11. So Miley will get the opportunity to pitch some important games during the final three weeks of the season.

If he stays on his current rotation, Miley will face the San Francisco twice before the end of September. How he fares in those appearances and whether he plays spoiler in the NL West race could help give him an edge over Todd Frazier in the race for NL Rookie of the Year.